1. Field of the Invention
This invention is related to the field of user interfaces and program controls. More particularly, this invention is directed to a method and apparatus For allowing simultaneous zooming and panning of content in a graphical user interface display.
2. Description of Background
A portion of the disclosure of this patent document contains material which is subject to copyright protect on. The copyright owner has no objection to the facsimile reproduction by any one of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
Many types of data have a broad range and a fine resolution. For example, a video clip is composed of a continuum of frames. The video clip can store up to a series of tens of thousands of frames. Thus, it has approximately five orders of magnitude. Similarly, a five second digital audio chip may require five orders of magnitude to access each bit sample. These types of data are often linear in the sense that there are starting and ending points and many Linked “frames” or points of data between the starting and ending points.
In order to edit a video clip, one needs frame accurate control over the entire medium. In other words, a user must be able to readily pick out one particular desired frame nestled among tens of thousands of frames. It becomes readily apparent that tasks such as adjusting key frames in an video film or manipulating audio samples, can quite time consuming and frustrating. What is needed is a method or apparatus which lets the user find and access one particular desired piece of data which is located among a broad range of data.
In the past, access to a particular point or frame of data was accomplished by using scroll bars. However, scroll bars typically can handle only two orders of magnitude. Consequently, a scroll bar would either need to be approximately twenty yards long in order to grant access to each frame of a video disk or provide a very compressed view of the frames in the video clip. The former user interface is impracticable, the latter would not be useful.
Another method used in the prior art was to implement VCR-type controls. This allows the user control over the entire range of data. However, these types of controls lack selectivity. For example, it would be difficult for a user to stop precisely on one particular desired frame or data point. The user would probably either overshoot or undershoot the desired frame or data point and would need to go back and forth searching for that particular frame or data point. What is needed is a method that gives the user control over a broad range, while giving the user random access to any particular piece of data within that range, especially at fine resolutions.
Yet another method used in the prior art to solve this problem is to provide one control for magnification of the data and another control for scanning at the selected magnification. One product utilizing has technique Is SoundEdit™ by Farallon Computing, Inc. However, this implementation has a drawback in that it requires two separate controls. A further disadvantage is that these two controls cannot be operated simultaneously. A user has to change the magnification control independently from the navigation control. Such a system results in wasted time and effort. Thus, what is needed is a method and apparatus for providing the user with easy and fluid interaction over varying magnification scales while simultaneously providing the user with the capability of scanning at that magnification scale.